By the reactive self-degraded template-directed synthesis and further carbonization, N- and O-doped carbonaceous nanotubes from conducting polymer (polypyrrole) precursor have been prepared. After being chemically activated by KOH, specially, with the weight ratio of KOH to polypyrrole nanotubes of 2 and 4, two samples of activated carbonaceous polypyrrole nanotubes (ACPN-2 and ACPN-4) with an uncapped morphology were obtained. The ACPN-4 possesses high heteroatom content (14.85%) and specific surface area (1226 m(2) g(-1)), and exhibits a reversible capacitance of 470 F g(-1) at the current density of 0.2 A g(-1), and 280 F g(-1) even at a higher current density of 10 A g(-1). Moreover, these nanotubular structured materials have also shown excellent cycling performance with no capacitance loss over 10,000 cycles. Furthermore, these carbonaceous nanotubes achieved a high CO2 adsorption uptake of 3.9 mmol g(-1) at 273 K and 2.5 mmol g(-1) at 298 K. (C) 2013 Published by Elsevier B.V.